The present invention relates to a mine-clearing apparatus. More particularly this invention concerns such an apparatus that can travel along the ground and neutralize mines in its path.
A standard traveling rock crusher as described in my U.S. Pat. No. 5,875,980 has a vehicle body adapted to travel along the ground in a horizontal travel direction, a drum mounted at a front end of the body and rotatable about a horizontal axis generally perpendicular to the direction, an array of radially outwardly projecting chisels mounted on the drum, and a plurality of angularly spaced breaker elements mounted on the drum between the chisels. A support is mounted on the body spaced back in the direction from a rear side of the drum and carries a plurality of vertically spaced breaker bars spaced from the drum. A drive is provided for forcibly rotating the drum about the axis in a sense with a front side of the drum moving upward and the rear portion of the drum moving downward for engaging the chisels and elements with rocks on the ground, picking up the rocks, and comminuting the rocks against the breaker bars.
Such a machine is used for scarifying roadways, clearing paths in a forest, or preparing ground for agricultural use. It picks up anything lying on the ground, mainly rocks, and crushes it, depositing the crushed material back on the ground.
For clearing mines an armored vehicle is provided that has a hardened front-end attachment that serves to trip and explode mines by applying pressure or vibrations. Such devices are fairly effective with mines on or close to the surface but occasionally fail to detonate more deeply buried mines, or mines that are set to explode only when compressed by a considerable weight. For such mines a plow arrangement is typically employed which tears up the path of the mine-clearing apparatus so much that it requires a separate regrading operation to make the path passable by normal vehicles.
It is therefore an object of the present invention to provide an improved mine-clearing apparatus.
Another object is the provision of such an improved mine-clearing apparatus which overcomes the above-given disadvantages, that is which surely detonates all mines in its path and which leaves a travelable path in its wake.
A further object is to provide a new method of clearing mines.
An apparatus for clearing mines set in the ground has according to the invention a vehicle body adapted to travel along the ground in a horizontal travel direction, a drum mounted at a front end of the body and rotatable in a rotational sense about a horizontal axis generally perpendicular to the direction, and an array of radially outwardly projecting chisels mounted on the drum. A support mounted on the body spaced from the drum is at least partially displaceable on the body radially relative to the drum. Springs braced between the body and the support hold the support in a standard position at a predetermined radial spacing from the drum and permit deflection of the support radially away from drum. A plurality of vertically spaced breaker bars are mounted on the support spaced from the drum. The drum is forcibly rotated about the axis in the rotational sense with a front side of the drum moving upward and a rear side of the drum moving downward for engaging the chisels and elements with rocks and mines on and in the ground, detonating mines in the ground, picking up the rocks and undetonated mines, and comminuting the rocks and crushing the undetonated mines against the breaker bars so that a mine detonating between the drum and the support will deflect the support against the springs away from the axis.
Thus with this system most mines will be detonated on initial contact with the drum. This will do no harm to this massively built structure. Any mines that fail to detonate will be picked up and crushed, which action will either detonate them or damage them so that they cannot detonate. The detonations that occur between the drum and the support will be absorbed by the spring-mounted breaker-bar support with no damage to the apparatus. The apparatus will therefore produce a clear swathe, leaving in its wake a relatively smooth path that can be counted on to be completely safe, as any mines have either been detonated or destroyed.
The support according to the invention is pivotal on the vehicle body about a support axis generally parallel to the drum axis. Means is provided for pivoting the support about its axis toward and away from the drum. The support has an upper end above the support axis and a lower end below the support axis. The springs include upper and lower spring packs respectively braced between the body and the upper and lower ends of the support. In addition an extensible hydraulic cylinder is braced against the body and is braced via another spring against the support so that extension or retraction of the cylinder displaces the support on the body. Furthermore another spring braced between the cylinder and the body allows detonations to be absorbed without damage to the hydraulic position-setting cylinder. For further protection of this hydraulic actuator a hydraulic accumulator is connected to the cylinder so that sudden movements of the support transmitted to the cylinder can be compensated for by the accumulator.
It is also possible for the support to be generally downwardly U-shaped and fit over the drum. The springs in this case include a plurality of spring packs spaced angularly relative to the drum axis.
The method of clearing mines buried in the ground therefore comprises the steps of displacing along the ground a traveling rock crusher modified with respect to its breaker-bar support as described above, forcibly rotating its drum about the drum axis in the rotational sense with a front side of the drum moving upward and a rear side of the drum moving downward so as to engage the chisels and elements with rocks and mines on and in the ground, detonate mines in the ground, pick up the rocks and undetonated mines, and comminute the rocks and crush the undetonated mines against the breaker bars, and absorbing a detonation of a mine between the support and the drum by elastic deformation of the springs.